Using air filters for filtering combustion intake air for internal combustion engines in motor vehicles, e.g. passenger cars, utility vehicles, working vehicles, vehicles for agriculture, as well as stationary generators and the like, is known. Such air filters generally include a housing, an air inlet, and an air outlet, wherein a removable and exchangeable primary filer element is arranged in the housing. Frequently, the housing includes a maintenance or access cover for access to the filter element housed in the interior in case maintenance is needed. To this end the filter element may be unmounted and either replaced by a factory-new filter element, re-furbished and re-used, or exchanged for a previously used but re-furbished filter element.
An air filter system that has an air filter housing and a serviceable air filter element is known from DE 20 2008 018 217 U1. The serviceable air filter element is positioned operationally ready within a housing interior. The air filter element has a filter body that extends between first and second closure caps. The filter body surrounds and defines an open filter interior. The first closure cap is an open closure cap that has an air flow aperture therethrough. The second closure cap is a closed closure cap that has an outer end surface. A housing seal arrangement is provided on the first closure cap and is designed to seal the air filter element against the air filter housing and to hold the air filter element in the housing. A projection/receiver arrangement is provided as a further retaining device that includes the first and second elements.
A first element of the projection/receiver arrangement is positioned on the outer end surface of the second closure cap. It is to be caused to engage with the access cover in a defined manner. A second element of the projection/receiver arrangement is positioned on the access cover. It has a serpentine ring element and may be either a ring projection or an annular receiver groove. The first and second elements of the projection/receiver arrangement are disposed engaged with one another to provide fixed retention of the air filter element on the second end. The first and second elements of the projection/receiver arrangement are non-rotatably engaged.
Normally the filter elements of air filters are exchanged after a certain operating period. Depending on how much dust there is, the service life for an air filter may be a few days, for instance in construction vehicles, up to several months in surroundings that are less dusty.
Reliable and trustworthy sealing of the filter element in a housing is important, especially when filter elements are exchanged frequently. The seal should be temperature-resistant and shake-proof. The seal for the filter element must be assured, even in systems or devices that are subjected to strong vibrations or shocks. At the same time, however, to the extent possible the filter element itself should not have any metal elements so that it is possible to remove heat from it with no problem.